Absorption-machine.



E. ALTENKIRCH & B. TENCKHOFF.

ABSORPTION MACHINE.

APPLICATION FILED AUG-9,1912.

Patented Apr. 25, 1916.

6 SHEETSSHEET I.

HGLi

WITNESSES INVENTOR' E. ALTENKIRCH & B. TENCKHOFF.

ABSORPTION MACHINE.

APPLICATION FILED AUG-9. 1912.

Patented Apr. 25,1916.

6 SHEETSSHE ET 2.

INV NT'U 5.

WCJ

E. ALTENKIRCH & B. TENCKHOFF.

ABSORPTION MACHINE.

APPLICATION FILED AUG-9, I912.

Patented Apr. 25, 1916. I

6 SHEETS-SHEET 3.

E. ALTENKIRCH & B. TENCKHOFF/ ABSORPTION MACHINE. APPLICATION-FILEDAUG-9. I912.

Patented Apr. 25, 1916.

6 SHEETSSHEET 4.

ELG- 7.

lI'II'INESSIES INVENTORS.

"av v E. ALTENKIRCH 61 B. TENCKHOFF.

ABSORPTION MACHINE.

APPLICATION FILED AUG-9. 1912.

" Patented Apr. 25, 1916.

WITNESSES Ni/ENTERS W Wm W ALTENKIRCH & B. TENCKHOFF.

ABSORPTION MACHINE. APPLICATION FILED AUG-9, I912- Patented Apr. 25,1916.

6 SHEETS-SHEET 6- INVENTO$ MWWL WETNESSES EDMUND ALTENKIRCH, 0FJE'RJEDERSDORF, NEAR BERLIN,

TENCKHOJEF, 0F JEEDJENAU, NEAR BERLIN, .1 :1

AND JBERNHARJD ANY.

TION-MACHIN 1E.

Specification of Letters Patent.

Patented Apr. 25, T916.

' Application filed August 9, 1912. Serial No. 714,285.

To all whom it may concern:

Be it known that we, EDMUND AL'rnN- Knicir and lienxnann TENCKHOFF, bothsubjects of the German Emperor, residing at Fredersdorf, near Berlin,and Friedenau, near Berlin, Germany, have invented certain new anduseful Improvements in Absor )tion-lilachines, of which the followingisii specification.

Tn hitherto proposed absorption machines, the refrigerating etl'ect mustbe notably smaller than the quantity of heat added to the generatoinorbOiler. The present invention causes an increase of therefrigeratingeffect. In special cases the refrigerating effect will be twice or threetimes greater than the refrigerating effect of the machines hithertoknown, so that the refrigerating effect will be greater than thequantity of heat required for its production.

Several embodiments of the invention are illustrated in the accompanyingdrawings, in which Figure 1 represents an absorption machine accordingto the present invention; Fig. 2, an absorption machine, generator andabsorber with a heat exchanger; Fig. 3 shows an absorption machine withoverlapping plant, where the production of work is the exclusive object;Fig. 5 shows a plant with auxiliary absorber and auxiliary evaporator,together with an exchanger; Fig. 6, a similar plant having threeabsorption machines working at different temperatures and independent ofeach other; Fig. 7 shows a combined multiple absorption machine forproduction of mechanical energy; Fig. 8, a heat plant with threeabsorption machines, and Fig. 9, a combined. multiple absorption machinefor production of mechanical energy.

Throughout the specification, the same characters denote the same parts.

The heat expenditure in'these machines is diminished by pumping the oldliquor, after having absorbed gas, back through the absorber in countercurrent, so thatlthe rich liquor assists in cooling the absorber beforeleaving it, which it does at the approximately initial temperatureof theabsorber, '1". c. the temperature at which the weak liquid entered. Thiscauses the rich liquid in the exchanger to be heated to a highertemperature, than it is possible to do temperatures; Fig. 4, a similarwithout this counter current of the liquor. It Wlll also be advantageousto send the hot weak liquor back before its leaving the generator incounter current through the latter; As a consequence, the rich liquorWill enter the rectifier with a lower temperature, which causes betterdrying of gas and at the same time a smaller expenditure of heat to addto the generator.

Fig, 1 shows an absorption machine ar ranged according to the presentinvention. The cold rich liquor is forced from the absorber a at a bythe pump 6 into the piping f and goes back through the absorber incounter current entering at c taking heat therefrom before leaving.- ByWay of pipe f the liquor then enters the exchanger p at f and cools thehot weak liquor entering at g and coming from the generator 6 afterwhich it is led through pipe 19 and enters the top of the generator 5.Here it descends, gradually becoming denser as distillation proceeds,and enters the pipe 9 at retraverses the generator 6 and passing in atis then forced through exchanger 7) and pipe 71 to absorber a. Itwill-thus be seen that the coiled pipe 9 actually forms a part of theabsorber. c is the condenser, (I the evaporator or refrigerator, h thesteam coil, 11 the cooling water system and n the brine system.

In the arrangement just described, distillation is supposed to be onlysmall so that a separate exchanger is still advantageous. The advantagesconsequent on leading the liquors in counter current will be stillgreater if distillation is carried farther. ltlachines suitable for thispurpose are well known and may be easily adapted for the counter currentsystem of liquors. Thus let it be supposed that distillation is carriedto such an extent that the Weak liquor coming from the generator absorbsgas at a temperature which causes distillation of the rich liquor in thegenerator, in other words that the initial temperature of the generatorat its top is the same as the initial temperature of the absorber. Theirthe temperature of the iich liquor leaving the absorber, equalsapproximately the initil) lllld initial temperature of the absorber, sothat a separate exchanger will be superfluous. Fig. 2 represents such anabsorption machine generator and absorber worklng in the mannerdescribed, the pipes g and f liaving no transferring connection, otherreference characters corresponding to those used in Fig. 1. The pipe 9in this construction leading directly to the absorber a which it entersat 1 v In such counter current absorption machines as described above itis possible to obtain a better coefficient of performance. It is stillimpossible however to reach the coefficient of performance equal to 1.Now this cocfiicient of performance 1, will be reached by carrying thedistillation farther than supposed in the embodiment illustrated in Fig.2. If this is done the weak llquor 18 still unsaturated under the lowerpressure in the absorber at a higher temperature than the initialtemperature of the generator. Absorption begins at temperatures thatcause evolution of ammonia in the generator. If heat exchange is nowmade between the parts of absorber and generator at approximately equaltemperatures, the considerable heat of absorption evolved in theabsorber, throughout this range of temperature, is immediately added tothe heat of the generator, so that the amount of heat to be supplied tothe generator by the heating coil for the same cooling effect will berelatively smaller. At the same time the consumption of heat bydistillation in the generator cools the hottest part of the absorber.Consequently the cooling effect required from the cooling water coil inthe absorber will be smaller. The higher the final temperature of thegenerator is taken, the greater is the coefficient of performance. Theheat exchange between generator and absorber may be effected by directcontact between the chambers or by circulating liquids. Fig. 3represents such an absorption machine with overlapping temperatures, thereference characters corresponding to those in the previous figures. Therich liquor does not go back through the whole absorber a, but leaves itat r with approximately the initial temperature of the generator 6 andthen enters the latter. It should namely be remembered that the absorbercontinues as a coiled pipe 9 in the upper part of the distillatingportion of the generator I). In the same way the poor liquor does notgoback through the whole generator I) but leaves it at s, withapproximately the initial temperature of the absorber which it thenenters through pipe 6*. Cooling pipes a pass through only part of thelength of the absorber 0, namely to r. On the other hand the steamheating coils h pass along the whole length of the generator I), becausethe amount of heat conenter the latter.

sumed in the generator will be greater at its cold end than at its hotend and likewise the amount of heat produced by absorption is greater atlow temperature, so that the consumption and the production of heat areunequal to those parts of the machine, which are heat exchanging. Thisimproved absorption machine is also advantageously employed foreconomical production of power for miscellaneous use. For this purpose apart or the whole of the gas evolved in the generator is sent into aWorking cylinder instead of into the condenser and is afterward made toenter the absorber. The production of work may thus be the exclusiveobject of the plant.

In Fig. 4, 0 represents the working cylinder of an engine. The vaporcoming from the generator I) enters this cylinder and then goes to theabsorber a through the pipe 8 after first having passed through a coilin the generator. lVith this new.overlapping of temperature it will beadvantageous to operate without leading the liquors in counter currentthrough the chambers and other parts, especially if differences inpressure are only small. Naturally the advantage will be greater, ifcounter current is made.

These absorption machines described above, work as machines in a mannercon trary to machines of earlier systems, having a coefiicient ofperformance which increases, as the difference of temperature betweenthe condenser and refrigerator decreases, caused by more overlapping oftemperatures, the end temperature of the refrigerator being constant.This arrangement has however, certain disadvantages, as for instance,the high pressure caused by the vapor pressure of the ammonia in thecondenser at the given cooling water temperature. To overcome thisdefect, the simplest way is to refrigerate by absorption and gasgeneration instead of by condensation and evaporation. Machines for thispurpose are well known but owing to the improper circulation of theliquors, the losses in these old machines are greater than with thearrangement of condenser and refrigerator. The losses will howeverbecome small if the condenser is replaced by an auxiliary absorber, andthe refrigerator replaced by an auxiliary evaporator operating on thecounter current principle as described above. The rich liquor from theauxiliary absorber is conducted in a heat exchanging manner and incounter current through the auxiliary evaporator to its coldest end andthen made to enter while the weak liquor is conducted'in a heatexchanging manner and in counter current through the auxiliary absorberto its hottest end and made to then Fig. 5 shows the scheme of such aplant with auxiliary absorber c and memes? auxiliary evaporator 03together with an exchanger p. The gas coming from the generator b isabsorbed in the auxiliary absorber 0 The enriched liquor leaves thisauxiliary absorber by the piping Z passing through the lower exchanger2) where it exchanges heat with the liquor coming through the pipes m, mand pump from the auxiliary evaporator (Z passes the latter by Way ofpipe Z in counter current to its coldest end, and then enters it througha regulating valve J. The distilled liquor is forced by the pump i intothe piping m and goes into the auxiliary absorber 0 after having passedthe exchanger p, and enters the latter at its hottest end. If thedistillation in the auxiliary evaporator 0Z is carriedon down to .theinitial temperature of the cooling water, that is, the final temperatureor final concentration of the auxiliary absorber 0 a separate heatexchanger is not required. The initial temperature of the auxiliaryabsorber is the same in this case as the initial temperature of thegenerator. It seems that cooling efiect produced at a temperature alittle below that of the cooling water is of no value. But this etl'ectis produced without further expenditure of heat and is thus of value forpre-cooling rooms and the like.

If it is required to produce low temperatures with small difi'erence ofpressure, it is necessary to cool the auxiliary absorber by means of apart of the cold produced in the refrigerator. The lowest temperature ofthe auxiliary absorber lies then below the highest temperature of theauxiliary evaporator (Z That is to say the temperatures overlap. Thisarrangement is shown in Fig. (3. The pump forces the distilled liquorthrough pipe 7.: into the auxiliary absorber which it enters at thepoint L where the temperature corresponds to its own highesttemperature, the liquor going then through the piping m in countercurrent to the hot end of the auxiliary absorber 0" where it enters thesame at mi. The liquor strengthened in the. auxiliary absorber 0". goesthrough the pipe I from its cold end at Z" into the auxiliary evaporator(1, which it enters at the point where the temperature corresponds toits own lowest temperature and runs in counter current through the sameand finally enters it at The cooling water passes in the pipe 2'- onlythrough the hotter part of the auxiliary absorber the cooler part beingcooled by communication through pipe j with the auxiliary evaporator(I5. l seful cooling effect is produced only at the coldest end of theauxiliary evaporator and is transferred to the brine by means of thecoil '22. The auxiliary absorber-m and the auxiliary evaporator (i thuspartly exchange their heat. In this way the lowest temperature of theauxiliary absorber can be brought considerably below the initialtemperature of' the cooling water and very low temperatures, even Withcooling water of high temperature, obtained without an excessiveincrease of pressure. The heat exchange may also be effected bycirculating liquid. For instance the brine returning from the cold roomsmay be forced in counter current through the coldest parts of theauxiliary absorber 0 instead of first entering the refrigerator. It thuscools the auxiliary absorber 0 below the initial temperature of thecooling Water and enters the auxiliary evaporator at a hotter point ofit. It is possible also to drive the auxiliary absorber c and auxiliaryevaporator (Z as described above by means of a compressor.

A. further possibility to make the coetticient of performance greaterthan unity, in absorption cooling machines, consists in making use ofthe improvement shown in Fig. 1 with id of that shown in Fig. 4, that isto say, with the machines having auxiliary evaporator and Without theuse of overlapping of temperature, as shown in Fig. 3. The ammonia vaporleaving the refrigerator d, see Fig. 7, has at the initial temperatureof the refrigerator, for instance, 10 C., still a considerable pressure,for ammonia about 3 kilog. per square cm. This gas, instead of passingdirect to the absorber uof an absorption machine enters at :1 anauxiliary absorber r through pipe with which is associated an auxiliaryevaporator 2 through the intermediary of a pipe In this chamber the gaswill evolve once more the same quantity of cold at a pressure of say 1kilo per square cm. The gas leaving the auxiliary. evaporator by way ofpipe .2 now goes into the absorber a of the absorption machine as shownin Fig. 7. Continuing in this way it is possible to provide for thisabsorption of the gas coming out of the re frigerator (l, which willgive a third stage. The number of stages possible depends on the fall oftemperatures required and also on the temperature of the cooling wateravailable. Each additional stage produces without any considerablyincreased expenditure of heat. nearly the same cooling effect as thefirst stage, and the cooling etliciency increases with the number ofstages. It is of advantage by this type to provide a rectifier.

lt is obviously advantageous to arrange machines to work in the newmanner in several stages whatever type of the known absorption machinesis used. Using. however, partly or entirely the improvements shown inFigs. 1 and 4, the advantage will be still greater.

It is preferable for a maximum coetlicicnt of performance, to add theheat to the generator at a temperature as high as possible.

To'attain this end, three absorption machines are arranged to Operate atdifferent temperatures independent of each other. In S the threemachines have respectively the following parts: absorbers a a, agenerators b b b auxiliary absorbers c (1", c, refrigerators d (Z (Zexchangers 72 p, connecting pipes Q01, 10 Q03 besides parts similar tothose already described. The three machines operate in such manner thatthe auxiliary absorber 0 see Fig. 8, and the absorber a of the secondmachine stand in heat transferring connection through pipes 10 with thegenerator 6 of the first machine. The heat produced in absorber u? andauxiliary absorber 0 is thus conducted into the generator 71 of thefirst 1naehine.to which end the temperatures must stand in suitablerelation to each other. As is always the case, the heat generated in theauxiliary absorber or condenser c and the absorber a together is greaterthan the heat absorbed in the generator by the amount of the producedcooling effect. The heat absorbed in the generator 71 of the secondmachine, to produce the same cooling effect, in the refrigerator of thefirst, can thus be smaller by this amount. The use of this excess heat.to heat the generator of another machine, also enables the coetlicientof performance of .absorption machines to be raised above unity. Thecooling effect of the refrigerattnd of the second machine may be used tocool the auxiliary absorber of the first machine, thus diminishing thequantity of cooling water required. The refrigerator (i of the thirdmachine can be heated by means of any low temperature waste heat, asshown by the pipes h, [L2 which represents additional heating coils. Thecondenser or auxiliary absorber c" and absorber J of the third machineare in heat transferring connection with the generator of the secondmachine through pipe 10 As a consequence, the heat expended to producethe same cooling etl'ects is still smaller.

The relative dimensions of the machines can be such that the excess heatproduced in the. one is sufiicientto heat the generator of the other.01' in addition the heat of the exhaust gases of the furnace can beutilized.

The pressure in each single machine may be chosen at will. Generally themultiple absorption machines require the provision of large surfaces forheat transference and this influences the cost of manufacture. If thepressure in the auxiliary absorber and evaporator of the first machineis the same as the pressure in the auxiliary evaporator and absorber ofthe second, the degrees of concentration are equal, the temperaturesalso being equal. Consequently the corresponding chambers may be unitedand the dimensions for equal output become considerably smaller. Theabsorber (L2 of the second machine is then superfluous and the generatorof the first can be of about half its size. In the same way theauxiliary evaporator 0* of the second machine is superfluous and theauxiliary absorber of the first machine can be smaller. Intheunitedchambers a considerably smaller quantity of liquor is circulating, thequantity circulating in the combined system being equal to thatcirculating previously in the first machine alone, although the heatconsumption for a given refrigerating eifect has become much smaller.Fig. 9 shows such a combined multiple absorption machine adapted for theproduction of mechanical energy. 0 is the working cylinder supplied withvapor from the generator and the refrigerator d. The working cylinderdelivers the expanded vapor into the absorber a through pipe 0 forced bythe pump a into a pipe f which leads the strong liquor to the threegenerators. The weak liquor is returned in the usual manner to theabsorber a. The liquors coming from the different chambers are to beconducted separately, or otherwise the pressure of the highertemperature chambers must be throttled in several stages by valves. notshown in the drawing. The gases generated in the last two generators 7F7) pass into the corresponding auxiliary absorbers c" c and are thereabsorbed. The liquors circulate in the same way as before. The auxiliaryabsorber corresponding to the. first generator is replaced, when themachine is to develop mechanical energy, by an auxiliary evaporator (1,the heating of which is effected as shown in the drawing by warmedcooling water from the absorber a. The heat coil h as indicated in thisarrangement, runs through the last generator only. In this way it ispossible to attain a very high temperature and consequently a goodutilization of heat. The new arrangement is of great benefit even whenapplied to machines of known types. The new arrangement of leading theliquors through the various chambers in counter current as described,will however, still fun ther increase the advantages.

The described principle of the reversible absorption machine and itsamplification is not confined to machines using ammonia liquor asworking fluid. lVithout change it may be applied to machines using anyother binary or more complicated mixture.

Claims:

1. An absorption machine for developing cold. heat or mechanical power,said machine comprising a enerator and an absorber. a heat duct tor saidgenerator and cooling duct for the absorber; conduits for said absorberleading rich liquor first in one and then in the opposite directionthrough The enriched liquor is Ill mate? the absorber, pipestransferring the liquor from the absorber to the generator, a collectorcoil for taking up the liquor in the generator and returning it, afterconcentration to the absorber whereby the liquor is made to traverseboth the absorber and the generator in two opposite directions.

2. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator and an absorber, a heat duct forsaid generator and cooling duct for the absorber; conduits for saidabsorber leading rich liquor first in one and then in the oppositedirection through the absorber, pipes transferring the liquor from theabsorber to the generator, a collector coil for taking up the liquor inthe generator and returning it, after concentration to the absorber, aheat exchanger inserted between said coil and said absorber, whereby theliquor is made to traverse both the absorber and the generator in twoopposite directions.

3. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator and an absorber, a heat duct forsaid generator and cooling duct for the absorber; conduits for saidabsorber leading rich liquor first in one and then in the oppositedirection through the absorber, pipes transferring the liquor from theabsorber to the generator, a collector coil for taking up the liquor inthe generator and returning it, after concentration to the absorber, aheat exchanger inserted between said coil and said absorber, and 'meansfor circulating the liquor, whereby the liquor is made to traverse boththe absorber and the generator in two opposite directions.

4=. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator and an absorber, a heat duct forsaid generator, and cooling duct for the absorber; conduits for saidabsorber leading rich cold liquor first in one and then in the oppositedirection through the absorber, pipes transferring the liquor from theabsorber to the generator; a collector coil for taking up the liquor inthe generator and returning it, after concentration to the absorber, aheat exchanger inserted between said coil and said absorber, and meansfor circulating the liquor, whereby cold rich liquor absorbs heat whileretraversing the absorber, thereupon cools hot weak liquor encounteredin the exchanger, then on descending the generator becomes denserthrough distillation then retraverses the generator through said coil,finally returning through the exchanger to the absorber.

5. An absorption machine for developing sorber, a heat duct for saidgenerator and cooling duct for the absorber; conduits for said absorberleading rich liquor first in one and then in the opposite directionthrough the absorber, pipes transferring the liquor from the absorber tothe generator, a collector coil for taking up the liquor in thegenerator and returning it, after concentration to the absorber, aworking cylinder for an engine inserted between said coil and saidabsorber, whereby the generated gas is made to enter said cylinder.

6. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator and an absorber, a heat duct forsaid generator and cooling duct for the absorber; conduits for saidabsorber leading rich liquor first in one and then in the oppositedirection through the absorber, pipes transferring the liquor from theabsorber to the generator, a collector coil for taking up the liouor inthe generator and returning it, after concentration to the absorber, aworln'ng cylinderfor an engine inserted between said coil and saidabsorber and means for circulating the liquor, whereby the generated gasis made to enter said cylinder.

7. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator, a main absorber and an auxiliaryabsorber, a heat duct for said generator; and cooling duct for theabsorber; conduits for said absorbers leading rich liquor first in oneand then in the opposite direction through the absorbers. pipestransferring the liquor from the main absorber to the auxiliary absorberand then to the generator, a collector coil for taking up the liquor inthe generator and returning it, after concentration to the mainabsorber, whereby the liquor is made to traverse both the absorbers andthe generator in two opposite directions.

8. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator, :1 main absorber and an auxiliaryabsorber, a heat duct for said generator, and cooling duct for theabsorber; conduits for said absorbers leading rich liquor first in oneand then in the opposite direction through the absorbers, pipestransferring the liquor from the main a sorber to the auxiliary absorberand then to the generator, a collector coil for taking up the liquor inthe generator and returning it, after concentration to the mainabsorber, whereby the liquor is made to traverse both the absorbers andthe generator in two opposite directions, a heat exchanger insertedbetween said coil and one of said absorbers.

9. An absorption machine for developing cold, heat or mechanical power,said machine comprising a generator, a main aberator in two oppositedirections, a heat exchanger inserted between said coil and saidabsorber, and means for circulating the 15 liquor.

In testimony whereof we have afiixed our signatures in presence of twowitnesses.

EDMUND ALTENKIRCH. l) ERNH A RI). TENCKHOFF.

Witnesses -lrvomonzsmn IIAUPT, HENRY HAsrEn.

